tree b9992c37d4a4645e6282375c669ae1e771206a1c
parent c488c7f649106d09df76f697adccbe6e72520b26
author Kevin Wolf <kwolf@redhat.com> 1314365233 +0200
committer Kevin Wolf <kwolf@redhat.com> 1314621759 +0200

qemu-img: Require larger zero areas for sparse handling

By default, require 4k of consecutive zero bytes for qemu-img to make the
output file sparse by not issuing a write request for the zeroed parts. Add an
-S option to allow users to tune this setting.

This helps to avoid situations where a lot of zero sectors and data sectors are
mixed and qemu-img tended to issue many tiny 512 byte writes.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>